Option variable
ratfacDefault value: false
When ratfac is true,
canonical rational expressions (CRE) are manipulated in a partially factored form.
During rational operations the
expression is maintained as fully factored as possible without calling factor.
This should always save space and may save time in some computations.
The numerator and denominator are made relatively prime, for example
rat ((x^2 - 1)^4/(x + 1)^2) yields (x - 1)^4 (x + 1)^2),
but the factors within each part may not be relatively prime.
In the ctensr (Component Tensor Manipulation) package,
Ricci, Einstein, Riemann, and Weyl tensors and the scalar curvature
are factored automatically when ratfac is true.
ratfac should only beset for cases where the tensorial components are known to consist offew terms.
The ratfac and ratweight schemes are incompatible and may not
both be used at the same time.